Described by the English ornithologists PL Sclater and Osbert Salvin in 1869, it is a medium-sized species that has a length of 10.6–13 cm (4.2–5.1 in) and a mass of 18–20.5 g (0.63–0.72 oz).

The species shows slight sexual dimorphism, with the females being duller and having yellow-green in place of yellow on the head.

The emerald tanager makes cup nests out of moss, where eggs are laid in clutches of two.

The emerald tanager was first described as Calliste florida by the English ornithologists Philip Sclater and Osbert Salvin in 1869, based on a female specimen from Costa Rica that was collected by Julian Carmiol.

[4] Emerald tanager is the official common name designated by the International Ornithologists' Union (IOU).

[5] However, some authorities recognize populations from eastern Panama to Colombia and northwestern Ecuador as being a distinct subspecies, T. f.

Both sexes are similar in appearance, but the species shows slight sexual dimorphism, with females being duller and having yellow-green instead of yellow on the head.

It is also similar to the blue-whiskered tanager but can be distinguished by the latter's black face and throat and turquoise cheeks.

[7] The emerald tanager makes a sharp chip or tsip which may be repeated and which occasionally accelerates into a rapid twitter.

[8] The emerald tanager is found from southern Costa Rica to northern Ecuador; through Panama and Colombia.

In Costa Rica, arthropods make up a greater proportion of the diet during the breeding season.

The most commonly eaten fruits include those in the genera Miconia, Coussapoa, Cecropia, Ficus, Ilex, Tetrochidium, and Topobea.